BRZ vs S2000 vs Cayman S (my take)

[CSG Mike]

Originally Posted by Frost

2nd here.
One of the things they teach you in track school is steering using your throttle.

It's actually pretty easy to do - find a parking lot with enough space and do the following:

1- Go in a circle and KEEP YOUR WHEEL at a CONSTANT angle
2- Now try gassing harder - see what happens
3- Now try gassing less - see what happens

<SPOILER ALERT> If you gas more, your front tires have less traction due to the weight transfer to the back and will understeer. If you gas less, you will tuck into the turn.

I can cause the *exact* opposite to happen with a stock FRS/BRZ with very clean, smooth steering inputs.

off-throttle, the car will plow (natural suspension balance).
light throttle the car will plow (natural suspension balance).
on aggressive throttle the car will rotate (ran out of rear grip with a combination of lateral load + acceleration, vs lateral only in the front).

[Yoda]

Originally Posted by CSG Mike

I can cause the *exact* opposite to happen with a stock FRS/BRZ with very clean, smooth steering inputs.

off-throttle, the car will plow (natural suspension balance).
light throttle the car will plow (natural suspension balance).
on aggressive throttle the car will rotate (ran out of rear grip with a combination of lateral load + acceleration, vs lateral only in the front).

So much science to this and hate I all forms of physics. That's why I changed major from Areodynamics to IT in college Physics 2 with calculus I want my two semesters back

[EAGLE5]

I knew I wasn't crazy. It probably doesn't help when the trunk is empty of everything, including the spare.

[Tokay444]

Originally Posted by ZDan

No. Way.

Yes. Way.

[Tokay444]

Originally Posted by CSG Mike

I can cause the *exact* opposite to happen with a stock FRS/BRZ with very clean, smooth steering inputs.

off-throttle, the car will plow (natural suspension balance).
light throttle the car will plow (natural suspension balance).
on aggressive throttle the car will rotate (ran out of rear grip with a combination of lateral load + acceleration, vs lateral only in the front).

^this.

[ZDan]

Originally Posted by CSG Mike

This is very driver and car (and even setup) dependent...

What I wrote:
the general NATURAL behavior of performance and handling-oriented cars is power-on understeer and power-off oversteer.

"General/natural" meaning, this is the inherent nature of how the car will behave. Yes, driver inputs matter, but any driver carving a smooth arc with fixed steering will experience oversteer if he gets off the gas, and understeer (below the point of incipient wheelspin) if he gets on the gas. Outside of any stability controls or electronic diff intervention, anyway...

Setup does matter, I've driven cars that would just plow no matter what because the setup was hosed. Properly set up, power-on understeer and power-off oversteer is the general rule. This is what responsive-handling cars do.

[Frost]

Originally Posted by CSG Mike

I can cause the *exact* opposite to happen with a stock FRS/BRZ with very clean, smooth steering inputs.

off-throttle, the car will plow (natural suspension balance).
light throttle the car will plow (natural suspension balance).
on aggressive throttle the car will rotate (ran out of rear grip with a combination of lateral load + acceleration, vs lateral only in the front).

I was trying to be as simple as possible but I don't think I'm wrong... am I?

I haven driven the stock FRS/BRZ enough but I'd like to get in one with you and see what you are saying.

In my experience, I am always relative throttle position for car steering angle. In other words, at a certain position and at a certain throttle with a certain steering angle, lifting off to a certain degree or gassing to a certain degree with do xxx.

I loved my old MR2 for the tuck in at lift off but it would also bite me hard. The S2k reminds me of her.

[EAGLE5]

Mid-corner, tires squealing, light throttle, car totally stock but nothing in the trunk - 2013 FRS...
Lift some - nose tucks in
Add a little power - car starts going wide.
Add too much power - car goes wide as power comes on then spins (my problem = impatience and bad timing).

[Tokay444]

Corner entry, off throttle, at speed, front pushes.
Lightly roll in some throttle, no corrective steering action, line tightens.
More throttle still, rear oversteers, opposite lock is applied, inside front tire clips apex, full throttle, more opposite lock, big smile is adorned, corner exited while zeroing out opposite lock, driving out of corner completely straight and ready to grab the next gear.
My car is on stock suspension and currently rolling on 16 inch snow tires.

[CSG Mike]

Originally Posted by Frost

I was trying to be as simple as possible but I don't think I'm wrong... am I?

I haven driven the stock FRS/BRZ enough but I'd like to get in one with you and see what you are saying.

In my experience, I am always relative throttle position for car steering angle. In other words, at a certain position and at a certain throttle with a certain steering angle, lifting off to a certain degree or gassing to a certain degree with do xxx.

I loved my old MR2 for the tuck in at lift off but it would also bite me hard. The S2k reminds me of her.

You're at a stage where you control your steering with your steering wheel. You get your rear wheel grip to a level where you are comfortable and maintain (so that you don't go over the limit, and break the rear loose), and steer the car with the steering wheel, and as long as you don't go over the limit of the front, you have steering control. When you go over the limit, you understeer.

I max out my front wheel grip with the steering wheel every time, and then add to the rotation using the throttle. Because the front is always maxed out, I can only fine-tune the car's trajectory with the rear wheel. This results in a higher cornering speed.

Refer to this post.

Originally Posted by CSG Mike

Draw a free body diagram that illustrates the force exerted upon the car by the front and rear wheels, in a state of understeer, and in a state of oversteer. You'll note that the net forward acceleration vector of both diagrams are the same, but the net lateral acceleration vectors of the understeer car are subtractive, whereas the net lateral acceleration vectors of the oversteer car are additive. The degree of slip angle determines the net forward acceleration, and if the slip angles are identical, the forward acceleration is identical, regardless of under/over.

The only exception to this, is if a corner is shallow enough, that you can go WOT (or maximum acceleration in the case of higher powered cars), and still retain full traction. In that case, you use the steering wheel to control turning, because the front wheels alone have more grip than what you need to hold the corner, and all the rear grip can be used for acceleration.

[CSG Mike]

Originally Posted by Yoda

So much science to this and hate I all forms of physics. That's why I changed major from Areodynamics to IT in college Physics 2 with calculus I want my two semesters back

And to think I don't have a degree...

[WolfpackS2k]

Originally Posted by chaoskaze

all those have a ton of stuffs between you and the engine to dampen out the stuff getting to you. AND PORSCHES does not count, they are rear engine & super far away from you by nature, even MR like cayman is super isolated....hell even @ auto cross that thing is quiet as it can get...... and I was in a cayman R with door straps.... ...obviously I was like ".....shit.....really......? this quiet with this much performance? while drooling over the car afterwords..."

Let's just say they are dampened out everywhere & only let you feel "some" of it other then exhaust/intake sound. (which is enough ...afterall it's "sport & luxury" in one car type of thing, you really get what you pay for.)

I'm going to have to disagree with you here, at least part of your argument. I assure you that I can hear the engine very clearly while blasting up to redline in my Cayman. The clarify of the intake noise is quite good, and it's audibly noticeable when the Variocam adjusts the timing higher up in the rev range. I dunno how you can say the engine is more isolated than the BRZ. The engine air intake is literally less than 2 feet from your head and the engine physically is less than a foot from your body/head. More isolated??

[totopo]

Originally Posted by WolfpackS2k

I'm going to have to disagree with you here, at least part of your argument. I assure you that I can hear the engine very clearly while blasting up to redline in my Cayman. The clarify of the intake noise is quite good, and it's audibly noticeable when the Variocam adjusts the timing higher up in the rev range. I dunno how you can say the engine is more isolated than the BRZ. The engine air intake is literally less than 2 feet from your head and the engine physically is less than a foot from your body/head. More isolated??

maybe the r version doesn't have a noise pipe....

http://www.bargainteers.com/top-5-ca...-engine-noise/

[WolfpackS2k]

Originally Posted by totopo

maybe the r version doesn't have a noise pipe....

http://www.bargainteers.com/top-5-ca...-engine-noise/

Don't believe everything you read. Besides being 95% confident that the 981 Cayman has zero engine noise piped into the cabin, I'm 100% confident you shouldn't rely on a website that says the 2014+ Cayman has a V6 engine.

Also I can tell you with 100% certainty that no 987 Caymans have any engine sound tubes (that includes the Cayman R).